Adjustable support for film strip and slide projector



June 7, 1960 E. v. KOSKELA ,9

ADJUSTABLE SUPPORT FOR FILM STRIP AND SLIDE PROJECTOR Original Filed July 17, 1952 3 Sheets-Sheet 1 IN VEN TOR.

Elmer Vk'oskela BY 7 (W (mam/ A ttorneyS E. V. KOSKELA June 7, .1960

ADJUSTABLE SUPPORT FOR FILM STRIP AND SLIDE PROJECTOR Original Filed July 17. 1952 3 Sheets-Sheet 2 INVENTOR. Elmer Vfisl'cla BY @w), fwd

ATTURNEYS.

June 7, 1960 E. v. KOSKELA ADJUSTABLE SUPPORT FOR FILM STRIP AND SLIDE PROJECTOR 3 Sheets-Sheet 3 Original Filed July 17, 1952 700' sif I02 I I B v INVENTOR pm 1 Kflsklq M rm w w u L7 7 Aitorneg v ADJUSTABLE surronrron FILM srmr AND sum; rnomc'ron Elmer V. Koskela, 1525 N. Elston Ave., Chicago 22, Ill. Original application my 17 1952 set; No. .299 424. Divided and this application' Sept: 21, 1956, 'serfNo. 612,414 f .2 Claims. Cl. 248-11) particularly to a projector including' adjustable supporting means. The present application is a 'division of acopending application of Elmer V.- Koskela, Serial No.

299,424, filed Iuly l7, 1952, nowPatent No. 2,793,563. Althoughprior projectors are available for projecting either strip film or mounted film slides, it is often too expensiveto obtain machines 'for use with each type of film. It is particularly desirable to have a single machine capable of utilizing-both types offilm, sincematen'al such as educational data is often available only on either one or the other of the two types of film. I'Also, film projectors norm'allyutilized in the home or in educational institutions are operated by unskilledpersonnel so that both conversionfrom'one type of film feeding device to theother and'the operation ofeach of thefeeding devices must be simpleand'jeasilyaccomplished.

The object is toprovide a film projector in which the projecting apparatus iscapable of being automati cally adjusted to a desired position for projection.

In accordance with this and many other objects, one embodiment of the invention comprises a film projector including a base member on which is pivotally mounted a supporting plate carrying a housing and a focus lens support. porting either a strip film feeding means or a film slide feeding means in a position interposed between a light source enclosed within the housing and a focusing lens slideably carried by the focus lens support. The film strip feeding means includes a unitary lens positioning and masking device detachably mounted thereon, and a film advancing means which is adapted to be actuated either by manual rotation of a knob carried on the device or by means of a remote control actuating means. The film slide feeding means includes a U-shaped trough having a V-shaped supporting surface and within which a slideably mounted element is manually moved-to position slides in a position interposed between the light source and the focusing lens. This manually actuated feeding element is automatically returned to a loading position under the control of a spring interconnecting the feeding element with the U-shaped member.

The focus lens support of the projector is formed of a single integral casting, and is provided with a centrally apertured portion to slideably receive an adjustable focusing lens actuated by a concave rubber covered driving cylinder, and is also provided with a recessed upper from the enclosed source of light from reaching the eyes of the projector operator. The supporting plate, which is pivotally mounted to the base member, is provided with a spring loaded cam member which iscontrolled by threaded means carried by the base in order to adjust- ..gaged by: a pair'of spaced machine'bolts 190, onlyrlione ing the invention; and r Fig. 2 is a side elevational view, in partial section, of the projector shown in Fig. l.

Referring now to 'the drawings, there is showna film projector, indicated generally as 20, which includesga base portion 22 to which is pivotally secured .a table 24' having a housing 26 and a focus lens support 28v mounted thereon. The housing-26 encloses a sourceofzlighta'nd supports a collimating-lens 30 for focusing thisilight. to impinge upon a film 38 moved between the housing'26 andthe focus lens support 28. r The focus lenssupport 28includes an adjustable focusiing lens assembly'32 positioned in alignment with the is mounted on the housing 26- in a position interposed between this housing a'ndthe-focusing lens 32 carried by the support 28. The construction of the projection apparatus and of thefilm feeding means is shown and described in detail in the aboveidentified Koskela patent. To provide a pivotal mounting forthe table;,24 to permit vertical adjustment of the beamjprovide'dv by-the focusing lens 32, the supporting table 24 isthreadedly-enof which is shown in thedrawings. A coil spring 192 is interposed between a lower surface of the upper wall of the base 22 and the head of each of the machinebolts so as to resiliently urge these bolts in a downward direction and, accordingly, to urge the lower edge of the supporting table 24 into engagement with the base 22. However, the provision of the coil spring 192 also permits the supporting table 24 and bolts 190 carried thereby to pivot relative to the base 22.

In order toautomatically control and produce a predetermined amount of inclination of the supporting table 24 relative to the base 22, a slightly offset bolt or shaft 194, depending from the table 24, is provided with'a cam surface 196. A sleeve 198 is secured to and depends from an upper wall of the base 22 and receives the lower end of the offset bolt194. A coil spring'200 is positioned between a lower surface of the top wall of the table 24 and the upper surface of the top wall of the base 22, and resiliently urges the table 24 in an upward direction relative to the base 22. A collar 202 is interposed between the coil spring 200 and the offset shaft 194 and serves to maintain spring 200 in a position concentric with the shaft 194.

In order to control the relative positions of the table 24 and the base 22, a threaded member 204, having a knob 206 thereon, is threadedly engaged within the sleeve 198 with one end of the member 204 in engagement with the cam surface 196. As the member 204 is rotated in a counterclockwise direction to move to the right, as viewed in Fig. 2 of the drawings, the offset shaft 194 and the table 24 are permitted to move in a counterclockwise direction under the resilient action of the'coil spring 200.

When a predetermined position is reached, the threaded member 204 is rotated in a clockwise direction to force the offset shaft 194 into engagement with the lower edge of the sleeve 198, andto'clamp this member in a predetermined position.

When it is desired to return the supporting table to a a normal horizontal position, the threaded member ,204-is Patented June 7,1950

' a sesses table 24 is manually depressed against the action of the spring 200. When the table 24 is positioned in the desired horizontal position, the threaded member 204 maybe rotated in a clockwise direction to engage the cam surface 196 and clamp the table 24 in this position. A

subsequent counterclockwise rotation of the threaded means 204 once again permits the shaft 194 to move upward, under the action of the spring 269, by producing a sliding engagement between the end of the threaded member 204 and the cam surface 196.

Therefore, the cam surface 196 and threaded member 204 cooperate to provide a fine control over the inclination of the projecting apparatus and also provide a means for positively securing the supporting table 24 in a desired position relative to the base 22. A nut 219 secured to the lower end of the shaft 194 engages the lower-edge of the sleeve 198 and thereby limits the allowable amount -of deflection of the supporting table 24 relative to the base .22. 7

While the present invention has been described in connection with the details of an illustrative embodiment, it should be understood that these details are not intended to be l-imitative of the invention except in so far as set forth in the accompanying claims.

What is claimed as new and desired to besecured by Letters Patent of the United States is:

1. In a projector, a base, projector supporting means pivotally mounted on the base, a sleeve depending from the base, cam means depending from the supporting means and extending into the sleeve, a coil spring positioned around the cam -means and interposed between the base'and the supporting means for urging the supporting means away from the base, threaded means carried by the sleeve and in engagement with the cam means for con rolling the movement of the support n me ns relative to the base, said threaded means being movable to force the cam means into engagement with the slee 'e to lock the supporting means in a desired position, and means carried by the cam means and movable into engagement with the sleeve'to limit the movement of the pporting means relative o the ba e- 2'. In a projector, afbase projector supporting means pivotally mounted on theba'se, cam means having a smooth cam surface depending from said supporting in a directiontoward said base, spring means interposed between saidbase and said supporting. means urging said supporting means away from saidrb ase, and adjustable means threadedly secured to said base and including a portion engaging said smooth cam surface, said smooth cam surface having such a contour that the mere application of a force on said supporting means in a direction toward said base causes movement thereof toward said base against the force of saidspring means regardless of the adjustment of said adjustable means, movement of said projecting means away from said base under the influence of said spring means being controlled solely by adjustment of said adjustable'means.

References Cited in the file of this patent UNITED STATES PATENTS UNITED -ST'ATES P'ATENT OFFICE CERTIFICATE OF CORRECTION Patent No; 2,939,659 June 7, 1960 Elmer V. Koskela It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the drawings, the present "Sheet 8, comprising Figs. 5,, 6, 7, 8, 9 and 10, should be canceled; in the heading to Sheet 1, line 3 for,"3 Sheets-Sheet 1'" read 2 Sheets- Sheet 1 and in the heading to Sheet 2, line 3, for

3 Sheets-Sheet 2": read 2 SheetsSheet 2 Signed and sealed this 20th day of December 1960.

(SEAL) Attest:

KARL H. AXLINE Attesting Officer ROBERT WATSON Commissioner of Patents 

